CN108882860B

CN108882860B - Tracking contact quality to vital sign measurement sensor

Info

Publication number: CN108882860B
Application number: CN201780019855.0A
Authority: CN
Inventors: R·S·巴拉姆; R·B·甘顿; S·迪基
Original assignee: Philips Healthcare Informatics Inc
Current assignee: Capsule Technologies Inc; Philips Healthcare Informatics Inc
Priority date: 2016-03-24
Filing date: 2017-02-27
Publication date: 2021-08-24
Anticipated expiration: 2037-02-27
Also published as: CN108882860A; EP3432771B1; WO2017165084A1; EP3432771A1; US20170273560A1; US10085639B2

Abstract

Various embodiments include a plurality of sensors, such as pulse oximeters, configured to track dynamic components of the sensors and take actions based on characteristics of the dynamic components. Some embodiments may include determining a gain applied to a signal of a sensor, determining whether the gain is discontinuous, and indicating a sensor measurement associated with the signal is of low quality in response to determining that the applied gain is discontinuous. Some embodiments may include determining a peak-to-peak voltage of an output of the sensor, determining whether the peak-to-peak voltage is within an acceptable peak-to-peak voltage range, and indicating that a measurement associated with the received signal is of low quality in response to determining that the peak-to-peak voltage is outside the acceptable peak-to-peak voltage range.

Description

Tracking contact quality to vital sign measurement sensor

Background

Continuous monitoring of vital signs with the ability to remotely monitor the status of a patient is an area of development and the ability to incorporate multiple measurement capabilities into a single small, unobtrusive patch that can be worn by the patient for multiple days at once (i.e., a body worn patch) is a desirable feature. One such vital sign measurement is a blood oxygen level reading, typically implemented by a pulse oximeter.

Pulse oximeters typically illuminate two different wavelengths of light through a patient's body part and measure the relative difference in the amplitudes of the raw and received light at the two different wavelengths. For example, one wavelength may be red light generated by a red Light Emitting Diode (LED) and another wavelength may be infrared light generated by an infrared LED. The relative difference in the amplitude of the raw red and raw infrared light and the received red and infrared light may be measured by a phototransistor. Blood with lower oxygen levels may tend to absorb less infrared light and more red light. Alternatively, blood with higher oxygen levels may tend to absorb more infrared light and less red light. Thus, a properly calibrated pulse oximeter may determine blood oxygen levels by emitting red and infrared wavelengths of light, as well as measuring the relative amounts of red and infrared light after the light has passed through a body part of a patient, such as a fingertip or earlobe. Additionally, the heart rate of the patient may be determined by a pulse oximeter based on measurements of received light. Movement of the patient and/or incorrect placement of the pulse oximeter may result in degradation of the blood oxygen level measurements made by the pulse oximeter as well as the heart rate measurements.

The waveform of the measurement light received by the pulse oximeter, also referred to as the received signal, has a high Direct Current (DC) (i.e., relatively static) component and a relatively low Alternating Current (AC) (i.e., dynamic) component caused by changes in the blood flow, the most important cause of such changes being the patient's pulse. Both the AC and DC levels of the received signal may vary widely depending on the color of the patient's skin, and/or the quality of the contact between the sensor element of the pulse oximeter and the patient's skin. As an example, the quality of contact between a sensor element of a pulse oximeter and a patient's skin may be affected by the placement of the sensor element, the state of the patient's skin (e.g., oily, dry, etc.), the user's hair, and the like.

To help mitigate the effects of varying AC and DC levels of the received signal, the pulse oximeter may include an Automatic Gain Control (AGC) loop for the sensor elements in the control algorithm. The AGC loop may amplify or reduce the voltage amplitude of the received signal to a level suitable for use by the measurement circuitry of the pulse oximeter, such as to within a threshold input level of an analog-to-digital converter (a/D converter).

In a similar manner, the waveform of the light transmitted by the pulse oximeter, also referred to herein as the transmit signal, may be controlled by the AGC loop to amplify or reduce the intensity of the light transmitted by the pulse oximeter to a level suitable for use by the measurement circuitry of the pulse oximeter. For example, the AGC loop may apply a gain to the LED light pulses transmitted by the pulse oximeter into the patient to amplify or reduce the intensity of the transmitted light to a level suitable for reception by the sensor element of the pulse oximeter.

Disclosure of Invention

Various embodiments provide methods for measuring quality of one or more measurements from one or more sensors. By way of example, the systems, methods, and devices of various embodiments may include a sensor (e.g., a pulse oximeter, an ultrasound sensor, a bioimpedance sensor, etc.) configured to track an Alternating Current (AC) component of a waveform of a measurement signal (e.g., a light signal, a sound signal, a bioimpedance signal, etc.) received by the sensor, and take an action based on a characteristic of the AC component of the waveform. Various embodiments provide methods for tracking sensor measurement quality.

Various embodiments may include obtaining, at a processor, a gain of a first signal generated by one or more sensors, wherein the one or more sensors are placed on a body of a subject, determining, at the processor, a gain of a second signal generated by the one or more sensors, and generating, at the processor, a contact quality based on a comparison of the gain of the first signal and the gain of the second signal, wherein the contact quality corresponds to a level of contact between the one or more sensors and the body of the subject. In some embodiments, generating the contact quality based on the comparison of the gain of the first signal and the gain of the second signal may include: the gain of the first signal, the gain of the second signal, and one or more thresholds are compared. Some embodiments may include adjusting one or more sensing modalities of one or more sensors based on the contact quality. In some embodiments, a low contact quality may indicate improper placement of one or more sensors, movement of the subject, or any combination thereof. Some embodiments may include filtering one or more measurements from the one or more sensors based on a comparison of the contact quality to at least one of the second thresholds, wherein the one or more measurements are associated with the second signal. In some embodiments, obtaining, determining, and generating may be performed after the change in applied gain has stabilized to take into account the subject's body skin type and color.

Various embodiments may include determining, at a processor, a peak-to-peak voltage of a received signal from one or more sensors, and generating, at the processor, a contact quality based on the peak-to-peak voltage and one or more thresholds, wherein the contact quality corresponds to a level of contact between the one or more sensors and a body of a subject. Some embodiments may include filtering one or more measurements from one or more sensors associated with the received signal based on a comparison of the contact quality to one or more thresholds. In some embodiments, the contact quality may indicate improper placement of the one or more sensors, movement of the subject, or any combination thereof.

Some embodiments may include a pulse oximeter having one or more sensors and a processor configured to perform the operations of the method described above. In some embodiments, the pulse oximeter may be integrated into the electronic patch.

Drawings

The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate embodiments of the invention and, together with the general description given above and the detailed description given below, serve to explain the features of the invention.

FIG. 1 is a component block diagram illustrating an electronic patch including a pulse oximeter that is placed on a patient, suitable for implementing various embodiments.

Fig. 2 is a circuit diagram illustrating circuitry for a pulse oximeter that may be adapted to be included on an electronic patch implementing various embodiments.

FIG. 3 is a process flow diagram illustrating a method for measuring quality of one or more measurements from one or more sensors.

FIG. 4 is a process flow diagram illustrating a method for determining a measurement quality of one or more measurements from one or more sensors.

Fig. 5 is a process flow diagram illustrating a method for indicating incorrect placement and/or movement of a pulse oximeter based on a determined quality level of a pulse oximeter measurement, according to an embodiment.

Fig. 6A is a process flow diagram illustrating a method for displaying an indication of improper placement and/or movement of a pulse oximeter based on a quality indication, according to an embodiment.

Fig. 6B is a process flow diagram illustrating a method for displaying an indication of incorrect placement and/or movement of a pulse oximeter based on a placement and/or movement indication, according to an embodiment.

FIG. 7 is a component block diagram of a computing device suitable for use with the various embodiments.

Detailed Description

Various embodiments will be described in detail with reference to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Reference to specific examples and implementations are for illustrative purposes, and are not intended to limit the scope of the invention or the claims.

The term "computing device" is used herein to refer to any or all of the following equipped with at least a processor and configured to communicate with a pulse oximeter, as described herein: cellular phones, smart phones, web pads, tablets, internet enabled cellular phones, Wireless Local Area Network (WLAN) enabled electronic devices, laptops, personal computers, smart apparel, and similar electronic devices.

Variations in the AC and DC levels of the received and/or transmitted signals may be caused by improper placement of the pulse oximeter and/or by movement of the patient after the pulse oximeter is placed on the patient. For example, incorrect placement of a pulse oximeter may result in the signal quality for the received signal being below a minimum threshold for acceptable readings. As another example, movement of the patient may cause one or more sensors of the pulse oximeter (such as sensor elements of the pulse oximeter) to lose contact with the patient's skin, resulting in the signal quality of the received signal falling below a minimum threshold for acceptable readings. Due to this effect on the quality of the received signal, incorrect placement and/or movement of the patient may result in degradation of the blood oxygen level measurement and the heart rate measurement by the pulse oximeter. The risk of incorrect placement and separation of the sensor from the skin due to patient movement is large for wearable pulse oximeters (e.g., electronic patches including pulse oximeters, smart clothing including pulse oximeters, hospital ID bands including pulse oximeters, headwear including pulse oximeters, etc.) compared to for wired stationary pulse oximeter devices. Additionally, because the wearable pulse oximeter may be placed on portions of the patient's skin that are covered by hair and/or are extremely oily, dry, etc., the risk of the sensor detaching from the skin is large for the wearable pulse oximeter as compared to for the wired stationary pulse oximeter. While a wired fixed pulse oximeter device may be placed on a hairless area of a patient's skin (e.g., a fingertip) in a hospital environment, it may be awkward to wear a wearable pulse oximeter on a hairless skin portion (e.g., a finger), and thus it may be integrated into a device that measures multiple vital signs that requires alternate placement on the patient's skin, which may need to be placed so that the patient feels natural and does not interfere with the patient's movements, and/or may be placed to meet the patient's fashion preferences. Thus, methods for accounting for (account for) incorrect placement, patient skin condition, and/or patient movement may enable a pulse oximeter to be integrated into a wearable form factor, such as an electronic patch, smart garment, hospital ID band, sports helmet, sports wristband or headband, and the like.

Systems, methods, and devices of various embodiments may include determining a gain applied to a current signal of one or more sensors, accessing a previous signal of the one or more sensors, determining a contact quality (e.g., a contact level) based on the current signal and the previous signal, and transmitting the contact quality. As an example, the contact level may be a value representing the proximity of the sensor to the body and/or artery of the subject, the contact level may be a value representing the amount of movement of the user, the contact level may be a value representing the accuracy of placement, or the like. Various embodiments may be applied to or used in conjunction with various sensors. A non-limiting example of a sensor in which various embodiments may be implemented is a pulse oximeter configured to track AC and/or DC components of waveforms of measurement parameters (e.g., various wavelengths of light, sound waveforms, bioimpedance signals, etc.) received by the pulse oximeter, which are also referred to as received signals. Using the example of a pulse oximeter, various embodiments may track the AC and/or DC components of the waveform of light generated by the pulse oximeter, also referred to as the transmit signal, and filter the measurements of the pulse oximeter based on the characteristics of the AC and/or DC components of the waveform. Transmitted and/or received signals having a discontinuous characteristic (i.e., transmitted and/or received signals having a characteristic that undergoes a large change from the selected allowed value from the last transmitted and/or received signal) may be indicative of an erroneous or poor quality reading by the pulse oximeter, such as an erroneous or poor quality reading caused by patient movement and/or incorrect placement of the pulse oximeter. Transmitted and/or received signals having characteristics above or below an acceptable range may be indicative of an erroneous or poor quality reading by the pulse oximeter, such as an erroneous or poor quality reading caused by incorrect placement of the pulse oximeter.

In some embodiments, blood oxygen level measurements and/or pulse measurements based on transmitted and/or received signals having non-continuous characteristics and/or characteristics above or below an acceptable range may be indicated by a pulse oximeter. In some embodiments, blood oxygen level measurements and/or pulse measurements based on transmitted and/or received signals having non-continuous characteristics and/or characteristics above or below an acceptable range may be filtered out by the pulse oximeter and not returned as valid measurements. In some embodiments, blood oxygen level measurements and/or pulse measurements based on transmitted and/or received signals having non-continuous characteristics and/or characteristics above or below an acceptable range may be both indicated and filtered out by a pulse oximeter. The indication and/or filtering of blood oxygen level measurements and/or pulse measurements based on transmitted and/or received signals having non-continuous characteristics and/or characteristics above or below an acceptable range may enable the pulse oximeter to account for improper placement and/or patient movement.

Various embodiments include an electronic patch with a pulse oximeter connected to a processor. In such embodiments, the processor may be configured to control operation of the pulse oximeter based at least in part on one or more waveform characteristics of the measured waveform of light received by the pulse oximeter (also referred to as the received signal), and/or one or more waveform characteristics of the waveform of light transmitted by the pulse oximeter (also referred to as the transmitted signal), which may be dedicated hardware, a programmable processor configured with processor-executable instructions, or a combination of dedicated hardware and programmable processor. In various embodiments, the waveform characteristics that may be monitored or used to control the operation of the pulse oximeter may include one or more of the gain applied to the received signal, the gain applied to the transmitted signal, and the peak-to-peak voltage of the received signal. In various embodiments, the processor may filter out one or more blood oxygen level measurements and/or one or more pulse measurements based on waveform characteristics associated with the transmitted and/or received signals used to generate the blood oxygen level measurements and/or pulse measurements. In various embodiments, the processor may be configured to indicate the quality of the blood oxygen level measurement and/or the pulse measurement to a remote device, such as a smartphone, based on waveform characteristics associated with the transmitted and/or received signals used to generate the blood oxygen level measurement and/or the pulse measurement. In various embodiments, the electronic patch may further include a coin-type battery or other low power source that provides power to the pulse oximeter.

When a subject first wears the device, there may be significant variation in the signal because the device takes into account the subject's body skin type and color until the gain applied by the device to the received signal stabilizes. In various embodiments, the operations discussed herein to determine the measurement quality of one or more measurements from one or more sensors may be performed after the signal associated with the body skin type and color of the subject in consideration has stabilized. In this manner, various embodiments may address only signals associated with processing movement of the sensor, rather than signals that take into account skin type and color.

Fig. 1 shows an embodiment electronic patch 106 that includes a sensor placed on the patient 102, such as on the skin surface of a finger of the patient 102. In various embodiments, the electronic patch 106 may be flexible and resilient such that placement and removal of the electronic patch 106 from the patient 102 does not damage the electronic patch 106. In the example shown in fig. 1, the electronic patch 106 includes pulse oximeter circuitry that includes a transmit signal output circuit 104 (e.g., circuitry including one or more light generator elements that output light such as one or more LEDs, one or more sound generator elements that output sound, etc.), and a receiver circuit 107 (e.g., circuitry including one or more phototransistors, circuitry including one or more microphones, etc.) that is configured to measure signals transmitted through the patient's skin and tissue that are emitted by the transmit signal output circuit 104. The transmit signal receiver circuit 107, alone or in combination with the pulse oximeter and/or other elements of the electronic patch 106 (e.g., the light output circuit 104), may constitute one or more sensors of the pulse oximeter.

The processor 108 may be connected to the transmit signal output circuit 104 and the receiver circuit 107. The processor 108 may be configured to control the operation of the pulse oximeter (e.g., the transmit signal output circuit 104 and/or the receiver circuit 107) and/or receive measurements from the pulse oximeter, the processor 108 may be dedicated hardware, a programmable processor configured with processor-executable instructions, or a combination of dedicated hardware and programmable processor. In some embodiments, the processor 108 may be configured with internal circuitry and/or processor-executable instructions to perform signal processing operations, such as filtering the received signal, applying automatic gain control to the transmitted and/or received signal, converting the received signal from an analog signal to a digital signal, and/or any other type of signal processing operation. In some embodiments, a filtering circuit (not shown) may be connected between the processor 108 and the receiver circuit 107, and the processor may be configured to control the filtering circuit to perform signal processing operations. For example, the processor may control the filtering circuitry to perform operations such as filtering the received signal, applying automatic gain control to the transmitted and/or received signal, converting the received signal from analog to digital, and/or any other type of signal processing operation. In such an embodiment, the filtered received signal may be output from the filtering circuit to the processor 108.

In an embodiment, the processor 108 may be further configured to determine the blood oxygen level and/or the pulse of the patient 102 based on signals received from a pulse oximeter (e.g., the transmit signal output circuit 104 and/or the optical receiver circuit 107). In an embodiment, the transmit signal output circuit 104, the receiver circuit 107, and/or the processor 108 may be connected to a low power source 105, such as a coin cell battery.

The processor 108 may intermittently turn the pulse oximeter (e.g., the transmit signal output circuit 104 and/or the receiver circuit 107) on and off to reduce the amount of current consumed from the low power source 105 as compared to continuously turning the pulse oximeter on (e.g., the transmit signal output circuit 104 and/or the receiver circuit 107). Turning on the pulse oximeter intermittently (e.g., transmit signal output circuit 104 and/or receiver circuit 107) may extend the life of the low power source 105, such as a coin-type battery, as compared to the life of the low power source 105 that can be achieved with a pulse oximeter that is always on.

The electronic patch 106 may also include a transceiver 116 connected to the antenna and processor 108 and the low power source 105. Using the transceiver 116, the processor 108 may establish a wireless connection (e.g.,

connected) and exchange data with a remote device such as a smartphone. Transceiver 116 is an example of one type of wireless connection device suitable for use in various embodiments, and other configurations of receivers and/or transmitters may be substituted for transceiver 116 to provide transmit and/or receive capabilities to processor 108 as desired for various different use cases for electronic patch 106.

Fig. 2 is a circuit diagram illustrating an embodiment circuit 200 for a pulse oximeter. Although fig. 2 shows components of a pulse oximeter, other types of sensors that may use various embodiments may include the same or similar components. In the embodiment shown in fig. 2, the circuit 200 may be integrated into an electronic patch worn by the patient, such as the electronic patch 106 described above. The low voltage power source may power the processor 108, or the processor may be powered by a separate power source (not shown). When switch 204a is closed, low power source 105 supplies capacitor 206 a. The switch may be located anywhere on the loop containing low power source 105 and switch 204a provided that the switch is able to electrically separate low power source 105 and switch 204 a. The processor 108 may control when the switch 204a is open or closed. For example, the processor 108 may close the switch 204a to allow the capacitor 206a to collect charge. The charge on the capacitor 206a may correspond to the voltage across the capacitor 206a via a known relationship. The voltage across capacitor 206a may be monitored by voltmeter 220. The voltmeter 220 may report the measured voltage to the processor 108.

When the voltage across the capacitor 206a reaches a predetermined limit, the processor 108 may open the switch 204a at an appropriate time to provide power to the transmit signal output circuit 104 to cause the transmit signal output circuit 104 to generate a transmit signal (e.g., various wavelengths of light, a sound waveform, a bio-impedance signal, etc.). As an example, the transmission signal output circuit 104 may include

switches

204b and 204c, and red LEDs 210a and infrared LEDs 210 b. The processor 108 may close the

switches

204b, 204c to allow charge to flow from the capacitor 206a to the red LED 210a and the infrared LED 210 b. The

switches

204b and 204c may be closed continuously to measure the absorbance at different wavelengths immediately.

Switches

204b, 204c may remain open while capacitor 206a is charging to prevent unnecessary consumption of low power source 105.

Resistors

222a, 222b may be connected in series with the red LED 210a and the infrared LED 210b to control the current through each

LED

210a, 210 b. The

resistors

222a, 222b may have the same or different resistances as each other. The

resistors

222a, 222b may provide greater control over the distribution of current from the capacitor 206a, thus helping to eliminate the need for higher current power supplies.

In an embodiment, the

switches

204b, 204c may be closed by the processor 108 to provide charge from the capacitor 206a to the red LED 210a and the infrared LED 210b for a period of time such that the

LEDs

210a and 210b emit red light 212a and infrared light 212b, respectively. After the period of time, the

switches

204b, 204c may be opened by the processor 108 to isolate the

LEDs

210a and 210b from the capacitor 206a, interrupting the flow of current from the capacitor 206a to the

LEDs

210a and 210b, and thus stopping the emission of light from the

LEDs

210a and 210 b. In this manner, light bursts may be generated from the red and

infrared LEDs

210a, 210b, and the current consumption of the circuit 200 may be minimized by turning on only the red and

infrared LEDs

210a, 210b for a brief period of time.

When sufficient current passes through the red and

infrared LEDs

210a and 210b, the LEDs emit red and

infrared light

212a and 212b, respectively. The light 212a, 212b propagates through a body part 244, such as a fingertip or an earlobe. The amount of light absorbed by the body part 244 may be a function of the amount of oxygen in the blood and the amount of blood in the body part 244 at the time of sampling. A body part 244 with a relatively large amount of oxygen will tend to absorb more infrared light 212b and less red light 212 a. A body part 244 with a relatively small amount of oxygen will tend to absorb less infrared light 212b and more red light 212 a.

After passing through the body part 244, the red light 212a and the infrared light 212b may be measured by a sensor, such as a photodetector 214, phototransistor, or photosensor of the receiver circuitry 107. Receiver circuitry 107 may include photodetector 214, switch 204d, and capacitor 206 b. Analysis of the absolute amplitude of the detected light signal by the processor 108, as well as analysis of the relative amplitudes of the detected red light and the detected infrared light, may reveal various attributes of the blood, such as the pulse profile and the amount of oxygen in the blood.

The photodetector 214 may be powered by a voltage source 224 a. The processor 108 may control the switch 204d that regulates the current from the voltage source 224a to the photodetector 214. When the switch 204d is closed, the photodetector 214 may transmit data to the processor 108. The processor 108 may synchronize the opening and closing of the switch 204d with the opening and closing of the

switches

204a, 204b, 204c such that the switch 204d is closed only when the photodetector 214 is receiving light. By opening switch 204d when the photodetector is not receiving useful data, the power demand can be further reduced. When the switch 204d is closed, current may flow from the photodetector 214 to the capacitor 206b and be stored in the capacitor 206b at the input of the processor 108.

The a/D converter of the processor 108 may measure the voltage at the capacitor 206 b. The AGC loop of the processor 108 may amplify or reduce the measured voltage amplitude before the voltage is passed to the a/D converter.

In one embodiment, the operation of the red LED 210a and the infrared LED 210b may be synchronized with the opening and closing of the switch 204d by the processor 108. Just before the red LED 210a and the infrared LED 210b are turned on by discharging the capacitor 206a, the processor 108 may close the switch 204D to allow the photodetector 214 to begin integrating the signals it receives, and may control the AGC loop and the a/D converter to take voltage measurements as soon as the red LED 210a and the infrared LED 210b are turned off. In an embodiment, the photodetector 214 may be a single device and may include two separate detectors tuned separately for each wavelength of light in use. The digital output of the a/D converter may be the output of the optical receiver circuit 107, which may be analyzed by the processor 108 as a measure of blood oxygen level.

The transceiver 116 connected to the antenna 233 may be coupled to the processor 108 and configured to establish a wireless connection, such as for example

Connected by low energy (Bluetooth LE)

Connect, and exchange data with a remote device (e.g., a smartphone). Transceiver 116 is an example of one type of wirelessly connected device suitable for use in various embodiments, and other configurations of receivers and/or transmitters may be substituted for transceiver 116 to provide transmit and/or receive capabilities to processor 108 as desired for various different use cases for circuit 200.

Although various embodiments are discussed with reference to an electronic patch including a pulse oximeter, such as electronic patch 106, the pulse oximeter may be integrated into other form factors, such as smart apparel (e.g., smart footwear, smart shirts, smart wristbands, smart necklaces, smart pants, etc.), smart furniture, vehicle (e.g., commercial and/or military aircraft, trains, buses, trucks, motorcycles, etc.) components (e.g., seats, steering wheels, armrests, etc.), stretchers, ambulances, beds, hospital ID bands, sports equipment (e.g., braces, handles, holsters, etc.), headwear (headbands, etc.), fixed medical readers, and so forth. Thus, the various embodiments may be applicable to any form factor including pulse oximeters.

FIG. 3 illustrates an embodiment method 300 for measuring quality of one or more measurements from one or more sensors. In an embodiment, the operations of method 300 may be performed by a processor (e.g., processor 108) comprising an electronic patch of a pulse oximeter, such as patch 106.

In block 302, a processor may perform operations including obtaining a gain of a first signal generated by one or more sensors, wherein the one or more sensors are placed on a body of a subject. For example, the processor may obtain the first signal by accessing previous signals of the one or more sensors by retrieving data associated with the previous signals from memory available to the processor.

In block 304, the processor may perform operations including determining a gain of a second signal generated by one or more sensors. For example, the second signal may be a current signal, such as the most recent waveform of a transmit signal output by the pulse oximeter from a signal generator element (e.g., LED), also referred to herein as a transmit signal, or may be the most recent waveform of a measured signal (e.g., light, sound, bio-impedance, etc.) received by a light sensor element (e.g., phototransistor) of the pulse oximeter, also referred to as a receive signal. The AGC loop may amplify or reduce the transmit signal and/or the receive signal, and the processor may determine the gain applied to the current signal by tracking the gain applied to amplify or reduce the voltage amplitude of the transmit and/or receive signal of the pulse oximeter, such as the gain applied by the AGC loop to the AC and/or DC components of the transmit and/or receive signal. The gain applied may be a value associated with the AGC loop, such as an amplification variable value, a number of bit counts, and the like. As part of determining the gain to apply to the current signal, the applied gain may be stored in a memory available to the processor. In this manner, a history of gains applied to one or more signals may be tracked by the processor.

In block 306, the processor may perform operations comprising generating a contact quality based on a comparison of the gain of the first signal and the gain of the second signal, wherein the contact quality corresponds to a level of contact between the one or more sensors and the body of the subject. As an example, the contact level may be a value representing the proximity of the sensor to the subject's body and/or artery, and the contact level may be a value representing the amount of movement of the user. The contact level may be a value indicating the accuracy of placement, or the like. Some embodiments may include determining a contact quality based on the current signal and the previous signal by comparing the current signal to the previous signal, and determining the contact quality based on the comparison of the current signal to the previous signal. Some embodiments may include comparing the current signal to a previous signal by comparing the current signal, the previous signal, and one or more thresholds. Some embodiments may include determining the contact quality based on the current signal, the previous signal, and the one or more thresholds by determining that the contact quality is high based on the current signal and the previous signal meeting or exceeding the one or more thresholds. Some embodiments may include determining a contact quality based on the current signal, the previous signal, and the one or more thresholds by determining that the contact quality is a low quality based on the current signal and the previous signal meeting or exceeding the one or more thresholds. Some embodiments may further include determining a quality level of one or more sensor measurements based on the current signal and a previous signal, and transmitting the quality level.

In some embodiments, the processor may determine a change in gain between a current signal and a previous signal of the pulse oximeter. The processor may determine the change in gain between the current signal and the previous signal by retrieving from memory available to the processor a value of gain applied to the previous signal, such as the gain applied to the previously transmitted and/or received signal, and subtracting the gain of the current signal determined from the gain applied to the previous signal. The absolute value of the difference between the determined gain of the current signal and the gain applied to the previous signal may be a change in gain. Alternatively, the absolute value of the difference between the determined gain of the current signal and the gain applied to the previous signal may be a change in gain over the time difference between the current signal and the previous signal. In this way, the change in gain may be an indication of the rate of change of gain. The gain applied to the previous signal may be a value of the gain applied to the most recent transmitted and/or received signal. Additionally, the gain applied to the previous signal may be an average of gains applied to a plurality of previously transmitted and/or received signals.

The processor may determine whether the change in gain is discontinuous. The discontinuous gain variation may be a variation of the gain that is large compared to the selected allowable value. The selected allowed value may be an absolute value associated with a maximum allowed difference between the gain applied to the current signal and the gain applied to the previous signal. Additionally, the selected allowed value may be the maximum allowed rate of change of gain applied to the current signal. The determined change in gain may be compared to a selected allowed value to determine whether the change in gain is discontinuous. The change in gain may be continuous when the change in gain is at or below a selected allowed value. A continuous gain may indicate that the AGC loop may be locked, which may indicate an acceptable or good quality reading by the pulse oximeter, such as an acceptable or good quality reading resulting from acceptable contact with the patient's skin and/or correct placement of the pulse oximeter. The variation in gain may be discontinuous when the variation in gain is above a selected allowed value. Discontinuous gain variations may indicate that the AGC loop may be unlocked, which may indicate erroneous or poor quality readings by the pulse oximeter, such as erroneous or poor quality readings caused by patient movement and/or misalignment of the pulse oximeter.

In response to determining that the applied gain is continuous, the processor may indicate that the pulse oximeter measurement associated with the current signal is of high quality. Indicating that the pulse oximeter measurement associated with the current signal is of high quality may include: an indication is sent to a remote device, such as a smartphone, that a blood oxygen level measurement and/or pulse measurement determined based on the sent and/or received signal with continuous gain applied is a high quality measurement. For example, the quality indication may be at

A link, such as a bluetooth Low Energy (LE) link, sent to a remote device. The indication that the blood oxygen level measurement and/or the pulse measurement is a high quality measurement may be sent with the transmission of the blood oxygen level measurement and/or the pulse measurement itself, and/or as a separate message. The indication sent by the processor that the blood oxygen level measurement and/or pulse measurement is a high quality measurement may be an indication of a scale of the quality of the measurement determined by the processor. As an example, the change in gain is at orThe amount of the allowable value that is below may be correlated by the processor on a scale, such as 1-10, and the processor may send the scale value as an indication to the remote device.

In response to determining that the applied gain is discontinuous, the processor may indicate that the pulse oximeter measurement associated with the current signal is of low quality. Indicating that the pulse oximeter measurement associated with the current signal is of low quality may include: an indication is sent to a remote device, such as a smartphone, that a blood oxygen level measurement and/or pulse measurement determined based on the sent and/or received signals having an applied gain above or below an acceptable gain range is a low quality measurement. For example, the quality indication may be at

Sent over a link to a remote device, such as a bluetooth LE link. The indication that the blood oxygen level measurement and/or the pulse measurement is a low quality measurement may be sent with the blood oxygen level measurement and/or the pulse measurement itself, and/or as a separate message. The indication sent by the processor that the blood oxygen level measurement and/or the pulse measurement is a low quality measurement may be an indication of a scale of the quality of the measurement determined by the processor. As an example, the amount by which the change in gain is above the allowed value may be correlated by the processor in a scale, such as 1-10, and the processor may send the scale value as an indication to the remote device.

In block 308, the processor may perform operations including sending the contact quality. In some embodiments, the processor may send the contact quality to a remote device such as a smartphone. In some embodiments, the processor may also send the blood oxygen level measurement and/or the pulse measurement determined based on the transmitted and/or received signals to a remote device such as a smartphone.

Some embodiments may further include determining a quality level of one or more sensor measurements based on the current signal and a previous signal, and transmitting the quality level. Some embodiments may further include adjusting one or more sensing modalities of one or more sensors based on the applied gain. In some embodiments, the quality level may indicate improper placement of the one or more sensors, movement of the subject, or any combination thereof.

In some embodiments, the processor may determine whether the applied gain is within an acceptable gain range. In this determination, the processor may compare the applied gain to a set of acceptable gain ranges or thresholds to determine whether the applied gain is within the acceptable gain range. The acceptable gain range may be a range of gain values extending from a minimum gain value to a maximum gain value. Alternatively, the acceptable gain range may be defined by a minimum threshold value and a maximum threshold value. The minimum gain value and/or the maximum gain value may be values associated with the AGC loop, such as amplification variable values, number of bit counts, and the like. The acceptable gain range may be selected such that the amplified or reduced transmit and/or receive signals resulting from the application of the AGC may have a voltage within a threshold input level of the a/D converter of the pulse oximeter.

In response to determining that the applied gain is within the acceptable gain range, the processor may indicate that the pulse oximeter measurement associated with the current signal is of high quality. Indicating that the pulse oximeter measurement associated with the current signal is of high quality may include: an indication is sent to a remote device, such as a smartphone, that the blood oxygen level measurement and/or pulse measurement determined based on the current signal having the applied gain within an acceptable gain range is a high quality measurement.

In response to determining that the applied gain is above or below the acceptable gain range, the processor may indicate that the pulse oximeter measurement associated with the current signal is of low quality. Indicating that the pulse oximeter measurement associated with the current signal is of low quality may include: an indication is sent to a remote device, such as a smartphone, that a blood oxygen level measurement and/or pulse measurement determined based on the sent and/or received signals having a gain range above or below an acceptable gain range is a low quality measurement. Such an indication that the pulse oximeter measurement is of low quality may be sent with the pulse oximeter measurement or as a separate message. A change in gain at or above the selected allowed value may indicate patient movement and/or malposition of the pulse oximeter that may affect blood oxygen level measurement and/or pulse measurement.

In an embodiment, the processor may optionally adjust the transmitted light based on the applied gain. Adjusting the transmitted light based on the gain may include: the intensity of the light sent by the pulse oximeter is adjusted based on the applied gain. For example, adjusting the transmitted light based on the gain may include: the processor of the pulse oximeter changes the amount of light emitted by the red LED and/or the infrared LED so that an appropriate amount of measured light is received (i.e., the received signal has a voltage amplitude above a minimum amount and/or below a maximum amount). Adjusting the transmitted light may be optional, as the transmitted light intensity may not be adjusted in each measurement cycle. For example, the light intensity may be increased or decreased only every ten or twenty measurement cycles. Additionally, adjusting the transmitted light may be optional, as the intensity of the transmitted light may not be adjustable for all pulse oximeters.

In some embodiments, the processor may determine whether the selected power state of the pulse oximeter is indicated to be "on". By determining whether the selected power state of the pulse oximeter is indicated as "on," the pulse oximeter may be intermittently turned on and off to reduce the amount of current consumed from the power source (such as a low power source) as compared to continuously turning the pulse oximeter on. The selected power state may be indicated in any manner, such as by a flag bit set in a memory location that indicates whether the pulse oximeter is to be powered on or off. In response to determining that the selected power state of the pulse oximeter is not on (e.g., is "off"), the processor may turn off the pulse oximeter power. The processor may power on the pulse oximeter in response to determining that the selected power state of the pulse oximeter is on.

Some embodiments may further include filtering one or more measurements from one or more sensors associated with the current signal based on a comparison of the contact quality to one or more thresholds. For example, in response to determining that the change in gain is discontinuous, the processor may filter the pulse oximeter measurements associated with the current signal. In various embodiments, filtering the pulse oximeter measurements associated with the transmitted and/or received signals may include filtering out all blood oxygen level measurements and/or pulse measurements determined based on the transmitted and/or received signals having a variation of gain that is not continuous. In various embodiments, filtering out pulse oximeter measurements may include not transmitting blood oxygen level measurements and/or pulse measurements determined based on transmitted and/or received signals exhibiting a discontinuous change in gain. By avoiding the transmission of blood oxygen level measurements and/or pulse measurements determined based on transmitted and/or received signals having discontinuous changes in applied gain, the pulse oximeter may avoid the transmission of degraded measurements and may avoid current consumption to the power supply. As another example, in response to determining that the applied gain is above or below an acceptable gain range, the processor may filter the pulse oximeter measurements associated with the current signal. In various embodiments, filtering the pulse oximeter measurements associated with the transmitted and/or received signals may include: all blood oxygen level measurements and/or pulse measurements determined based on the transmitted and/or received signals having an applied gain outside of an acceptable gain range are filtered out. In various embodiments, filtering out pulse oximeter measurements may include: blood oxygen level measurements and/or pulse measurements determined based on the transmitted and/or received signals having applied gains above or below the acceptable gain range are not transmitted. By avoiding the transmission of blood oxygen level measurements and/or pulse measurements determined based on transmitted and/or received signals having an applied gain outside of an acceptable gain range, the pulse oximeter may avoid the transmission of degraded measurements and may avoid current consumption from the power supply.

The method 300 may be performed repeatedly, such as with each measurement cycle.

When the subject wears the device for the first time, there may be significant variations in the signal because the device takes into account the skin type and color of the subject's body until the gain applied by the device to receive the signal stabilizes. In an embodiment, the operations of method 300 may be performed after the signal associated with the skin type and color that takes into account the subject's body has stabilized. In this manner, the operations of method 300 may address signals associated only with processing movement of the sensor, rather than signals that take into account skin type and color. For example, as soon as the device is placed on the subject, the processor may determine whether the change in applied gain has stabilized taking into account the subject's body skin type and color. In response to determining that the change in applied gain has stabilized to account for the skin type and color of the subject, the processor may perform the operations of block 302 of method 300.

FIG. 4 illustrates an embodiment method 400 of a method for determining a measurement quality of one or more measurements from one or more sensors. In an embodiment, the operations of method 400 may be performed by a processor (e.g., processor 108) comprising an electronic patch of a pulse oximeter, such as patch 106.

In block 402, a processor may perform operations including determining a peak-to-peak voltage of a received signal from one or more sensors. For example, the processor may determine a peak-to-peak voltage of a received signal that is the output of a light sensor of a pulse oximeter. The received signal may be a waveform from the output of a light sensor element (such as a phototransistor) of the pulse oximeter. In various embodiments, the processor of the pulse oximeter may track the peak-to-peak voltage of the AC component of the received signal. The peak-to-peak voltage may be tracked as a value such as voltage value, number of bit counts, and the like.

In block 404, the processor may perform operations comprising generating a contact quality based on the peak-to-peak voltage and the one or more thresholds, wherein the contact quality corresponds to a level of contact between the one or more sensors and a body of the subject. As an example, the contact level may be a value representing the proximity of the sensor to the body and/or artery of the subject, the contact level may be a value representing the amount of movement of the user, the contact level may be a value representing the accuracy of placement, or the like. Some embodiments may include determining the contact quality based on the peak-to-peak voltage and the one or more thresholds by comparing the peak-to-peak voltage to the one or more thresholds, and determining the contact quality based on the comparison of the peak-to-peak voltage to the one or more thresholds. In some embodiments, the processor may determine whether the peak-to-peak voltage is within an acceptable peak-to-peak voltage range. The processor may compare the peak-to-peak voltage of the AC component to an acceptable peak-to-peak voltage range. The acceptable peak-to-peak voltage range may be a range of peak-to-peak voltages extending from a minimum voltage to a maximum voltage. Alternatively, the acceptable peak-to-peak voltage range may be defined by a minimum threshold value and a maximum threshold value. The minimum voltage and/or the maximum voltage may be various types of values, such as a voltage value, a number of bit counts, and the like. In one embodiment, the acceptable peak-to-peak voltage range may be a minimum threshold value, and the acceptable peak-to-peak voltage may include any peak-to-peak voltage above the minimum threshold value regardless of the maximum voltage threshold value.

Some embodiments may further include filtering one or more measurements from one or more sensors associated with the received signal based on the comparison of the contact quality to the one or more thresholds. In some embodiments, the processor may filter the pulse oximeter measurements associated with the received signals in response to determining that the peak-to-peak voltage is above or below an acceptable peak-to-peak voltage range. In some embodiments, filtering the pulse oximeter measurements associated with the received signals may include: all blood oxygen level measurements and/or pulse measurements determined based on the received signal having a peak-to-peak voltage above or below an acceptable peak-to-peak voltage range are filtered out. In some embodiments, filtering out pulse oximeter measurements may include not sending blood oxygen level measurements and/or pulse measurements determined based on received signals having peak-to-peak voltages above or below an acceptable peak-to-peak voltage range. By avoiding the transmission of blood oxygen level measurements and/or pulse measurements determined based on received signals having peak-to-peak voltages outside of an acceptable range of peak-to-peak voltages, the pulse oximeter may avoid the transmission of degraded measurements, and may avoid current drain on a coin-type battery or other low power source that may power the pulse oximeter. In some embodiments, in response to determining that the peak-to-peak voltage is within the acceptable peak-to-peak voltage range, the processor may take no action to prevent recording or transmission of data, such as to a remote device (e.g., a smartphone).

In block 308, operations of like numbered blocks of method 300 described with reference to fig. 3 are performed to transmit the contact quality.

Some embodiments may further include determining a quality level of one or more sensor measurements based on the received signal, and transmitting the quality level. In some embodiments, the quality level may indicate improper placement of one or more sensors, movement of the subject, or any combination thereof. In response to determining that the peak-to-peak voltage is within the acceptable peak-to-peak voltage range, the processor may indicate that the pulse oximeter measurement associated with the received signal is: high quality. Indicating that the pulse oximeter measurements associated with the received signals are of high quality may include: sending an indication to a remote device, such as a smartphone, that a blood oxygen level measurement and/or pulse measurement determined based on a received signal having a peak-to-peak voltage within an acceptable range of peak-to-peak voltages is a high quality measurement. As an example, the amount of peak-to-peak voltage within the acceptable peak-to-peak voltage range may be correlated by the processor on a scale such as 1-10, and the processor may transmit the scale value as an indication to the remote device. In response to indicating that the pulse oximeter measurement is of high quality, the processor may determine a peak-to-peak voltage of the received signal for the next measurement cycle.

In response to determining that the peak-to-peak voltage is outside of the acceptable peak-to-peak voltage range, the processor may indicate that the pulse oximeter measurement associated with the received signal is of low quality. Indicating that the pulse oximeter measurement associated with the received signal is of low quality may include: an indication is sent to a remote device, such as a smartphone, that a blood oxygen level measurement and/or pulse measurement determined based on a received signal having a peak-to-peak voltage above or below an acceptable peak-to-peak voltage is a low quality measurement. As an example, the amount by which the peak-to-peak voltage is outside of the acceptable peak-to-peak voltage range may be correlated by the processor on a scale such as 1-10, and the processor may transmit the scale value as an indication to the remote device.

The method 400 may be performed repeatedly, such as with each measurement cycle.

Various embodiments may include filtering the pulse oximeter measurements based on the gain applied to the current signal and the peak-to-peak voltage of the current signal. For example, one or more operations of the method 300 described with reference to fig. 3 and the method 400 described with reference to fig. 4 may be performed in conjunction to filter pulse oximeter measurements based on the gain applied to the current signal and the peak-to-peak voltage of the current signal.

Various embodiments may include indicating the quality of the pulse oximeter measurement based on the gain applied to the received signal and the peak-to-peak voltage of the received signal. For example, one or more operations of the method 300 described with reference to fig. 3 and the method 400 described with reference to fig. 4 may be performed in conjunction to indicate the quality of the pulse oximeter measurement based on the gain applied to the received signal and the peak-to-peak voltage of the received signal.

Fig. 5 illustrates an embodiment method 500 for indicating improper placement and/or movement of a pulse oximeter based on a determined level of quality of a pulse oximeter measurement. In an embodiment, the operations of method 500 may be performed by a processor (e.g., processor 108) comprising an electronic patch of a pulse oximeter, such as patch 106. In various embodiments, the operations of method 500 may be performed by a processor in conjunction with the operations of methods 300 and/or 400.

In block 502, the processor may determine an indicated quality level. As an example, the processor may determine the indicated quality level based on a determined change in gain (e.g., a continuous change in gain to indicate that the quality level is high, a discontinuous change in gain to indicate that the quality level is low, etc.), based on a peak-to-peak voltage, by retrieving a stored quality level indication from memory, and/or by monitoring a transmission of a quality indication to a remote device such as a smartphone.

In determination block 504, the processor may determine whether the quality level indicates improper placement of the pulse oximeter and/or movement of the patient. In some embodiments, the indication of the blood oxygen level measurement and/or the quality of the pulse measurement may reflect the quality of the placement of the pulse oximeter and/or the amount of movement of the patient. For example, an indication of a blood oxygen level measurement and/or a low quality of pulse measurement may be an indication of an incorrect placement of the pulse oximeter on the patient and/or an indication that the patient moves such that the sensor element loses contact with the patient's skin. In some embodiments, the processor of the pulse oximeter may determine the quality of placement of the pulse oximeter and/or the amount of movement of the patient based on the quality of the blood oxygen level measurements and/or the determination of the pulse measurements on a relative scale based on the applied gain and/or peak-to-peak voltage. For example, the processor may determine whether the quality level indicates incorrect placement of the pulse oximeter and/or movement of the patient by comparing the quality level indication to a minimum quality threshold associated with incorrect placement of the pulse oximeter on the patient, and/or an indication that the patient has moved such that the sensor element loses contact with the patient's skin. A quality indication below a certain level may indicate that the pulse oximeter is not properly placed, and/or that the patient is moving which results in the sensor element losing contact with the patient's skin.

In response to determining that the quality level indicates correct placement and/or no patient movement (i.e., determining that block 504 is "no"), the processor may indicate correct placement and/or no movement occurred in block 506. In some embodiments, the processor may indicate correct placement and/or no movement occurring by sending an indication of the quality of the placement of the pulse oximeter and/or the amount of movement of the patient to a remote device such as a smartphone. For example, the processor of the pulse oximeter may send an indication (e.g., an "ok" message) that the placement of the pulse oximeter is acceptable and/or that no movement has occurred. As another example, the processor of the pulse oximeter may send a scale indication, such as a value between 1-10, reflecting acceptability and/or lack of movement.

In response to determining that the quality level indicates incorrect placement and/or unacceptable patient movement (i.e., determining that block 504 is "yes"), the processor may indicate incorrect placement and/or occurrence of patient movement in block 508. In some embodiments, the processor may indicate correct placement and/or no movement occurring by sending an indication of the quality of the placement of the pulse oximeter and/or the amount of movement of the patient to a remote device, such as a smartphone. For example, the processor of the pulse oximeter may send an indication that the placement of the pulse oximeter is incorrect (e.g., a "move" message). As another example, the processor of a pulse oximeter may send an indication (e.g., a "warning" message) that the patient moved such that the chat sensor element lost contact with the patient's skin. An indication that the placement of the pulse oximeter is incorrect and/or that the patient moves such that the sensor element loses contact with the patient's skin may be sent as a graduated indication, such as a value between 1-10, reflecting the quality of the placement (e.g., a high value indicates a better placement than a low value or vice versa) and/or the amount of movement (e.g., a high value indicates more movement than a low value or vice versa). In this manner, the scale may enable a user of a remote device, such as a smartphone, to determine the amount of movement and/or the level of degraded contact with the patient's skin that is required to properly place the pulse oximeter.

Fig. 6A illustrates an embodiment method 600 for displaying an indication of improper placement and/or movement of a pulse oximeter based on a quality indication. In an embodiment, the operations of method 600 may be performed by a processor of a computing device, such as a computing device in communication with an electronic patch (such as patch 106) that includes a pulse oximeter. In various embodiments, the operations of method 600 may be performed by a processor in conjunction with the operations of method 300, method 400, and/or method 600.

In block 602, the processor may receive a quality indication. As an example, the processor may receive a quality indication, such as patch 106, from a processor of an electronic patch that includes a pulse oximeter. For example, mass meansCan be at

Sent to the processor over a link, such as a bluetooth LE link. As an example, the quality indication may be a quality indication sent by a pulse oximeter in accordance with the operations of method 300, method 400, and/or method 500 described with reference to fig. 3, 4, and/or 5.

In determination block 604, the processor may determine whether the quality level indicates improper placement of the pulse oximeter and/or movement of the patient. In some embodiments, the indication of the blood oxygen level measurement and/or the quality of the pulse measurement may be an indication of the quality of the placement of the pulse oximeter and/or the amount of movement of the patient. For example, an indication of a blood oxygen level measurement and/or a low quality of pulse measurement may be an indication of an improper placement of the pulse oximeter on the patient, and/or an indication that the patient moves such that the sensor element loses contact with the patient's skin. In some embodiments, the processor may determine the quality of the placement of the pulse oximeter and/or the amount of movement of the patient based on the determined quality of the blood oxygen level measurement. For example, the processor may determine whether the quality level indicates incorrect placement of the pulse oximeter and/or movement of the patient by comparing the quality level indication to a minimum quality threshold associated with incorrect placement of the pulse oximeter on the patient, and/or an indication that the patient is moving such that the sensor element loses contact with the patient's skin. A quality indication below a certain level may indicate that the pulse oximeter is not properly placed, and/or that the patient is moving such that the sensor element loses contact with the patient's skin. In various embodiments, the quality indication may be a value indicating the relative quality of the measurement, on a scale such as 1-10, which indicates the quality of the blood oxygen level measurement and/or pulse measurement.

In response to determining that the quality level indicates correct placement and/or no patient movement (i.e., determining that block 604 is no), the processor may display a correct placement and/or no movement indication in block 606. In some embodiments, the remote device may display an indication of proper placement of the pulse oximeter and/or an indication that the patient is not moving as a message, graphic, audible command, or any other type of indication perceptible to a user of the remote device so that the user of the remote device may be notified of proper placement of the pulse oximeter and/or an indication that the patient is not moving.

In response to determining that the quality level indicates incorrect placement and/or patient movement (i.e., determining that block 604 is yes), the processor may display an incorrect placement and/or movement indication in block 608. In some embodiments, the remote device may display the indication of the incorrect placement of the pulse oximeter and/or the indication of patient movement as a message, graphic, audible command, or any other type of indication perceptible to a user of the remote device so that the user of the remote device may be notified of the incorrect placement of the pulse oximeter and/or the indication of patient movement. In this way, the user of the remote device may be prompted to take actions regarding the placement of the pulse oximeter and/or the movement of the patient, such as adjusting the placement of an electronic patch on the patient that includes the pulse oximeter.

Fig. 6B illustrates an embodiment method 610 for displaying an indication of improper placement and/or movement of a pulse oximeter based on the placement and/or movement indication. In an embodiment, the operations of method 610 may be performed by a processor of a computing device, for example, a computing device in communication with an electronic patch (such as patch 106) that includes a pulse oximeter. In various embodiments, the operations of method 610 may be performed by a processor in conjunction with the operations of method 300, method 400, method 500, and/or 600.

In block 612, the processor may receive a placement and/or movement indication. As an example, the processor may receive placement and/or movement indications from a processor of an electronic patch (such as patch 106) that includes a pulse oximeter. For example, the placement and/or movement indication may be at

Sent to the processor over a link, such as a bluetooth LE link. By way of example, placing and/or movingThe indication may be a placement and/or movement indication sent by the pulse oximeter in accordance with the operations of block 506 and/or block 508 of method 500 described with reference to fig. 5.

In determination block 614, the processor may determine whether the placement and/or movement indication indicates an incorrect placement or movement. In various embodiments, the incorrect placement and/or movement indication may be on a scale (such as a value of 1-10) indicating a relatively incorrect placement and/or movement that indicates an incorrect level of placement and/or a level of patient movement.

In response to being indicated a correct placement and/or no movement (i.e., determination block 614 no), the processor may display a correct placement and/or no movement indication in block 606, as described with reference to fig. 6A. In response to being indicated as incorrect placement and/or movement (i.e., determining block 614 — yes), the processor may display an incorrect placement and/or movement indication in block 608, as described with reference to fig. 6A.

An embodiment patch may be configured to transmit data to any of a variety of computing devices. For example, fig. 7 illustrates a computing device 700 suitable for use in various embodiments. The computing device 700 may exchange data from the electronic patches discussed above and may perform one or more of the operations of the

methods

300, 400, 500, 600, and/or 610 described with reference to fig. 3, 4, 5, 6A, and/or 6B. As an example, pulse oximeter measurements, quality indications, placement indications, and/or movement indications may be sent to computing device 700 from a processor of an electronic patch (such as patch 106) that includes a pulse oximeter. As another example, pulse oximeter control signals may be sent from the computing device 700 to a processor of an electronic patch (such as patch 106) that includes a pulse oximeter and an accelerometer.

In various embodiments, the computing device 700 may include a processor 701 coupled to a touchscreen controller 704 and an internal memory 702. Processor 701 may be one or more multi-core ICs designated for general or specific processing tasks. The internal memory 702 may be volatile or non-volatile memory, and may also be secure and/or encrypted memory, or unsecure and/or unencrypted memory, or any combination thereof. The touchscreen controller 704 and the processor 701 can also be coupled to a touchscreen panel 712, such as a resistive-sensing touchscreen, a capacitive-sensing touchscreen, an infrared-sensing touchscreen, and so forth.

The computing device 700 may have one or more wireless signal transceivers 708 for transmitting and receiving (e.g.,

WLAN, RF, cellular, etc.) and an antenna 710 coupled to each other and/or to the processor 701. The transceiver 708 and antenna 710 may be used with the above-mentioned circuitry to implement various wireless transmission protocol stacks and interfaces. The computing device 700 may include a cellular network radio modem chip 716 that enables communication via a cellular network, such as an eMBMS network, and is coupled to the processor.

The computing device 700 may include a peripheral connection interface 718 coupled to the processor 701. The peripheral device connection interface 718 may be configured solely to accept one type of connection or configured to accept various types of general or proprietary physical and communication connections, such as USB, firewire, thunderbolt, or PCIe. Peripheral device connection interface 718 may also be coupled to a similarly configured peripheral device connection port (not shown).

The computing device 700 may also include a housing constructed of plastic, metal, or a combination of materials for containing all or some of the components discussed herein. The computing device 700 may include a power supply 722, such as a disposable or rechargeable battery, coupled to the processor 701. The rechargeable battery may also be coupled to the peripheral device connection port to receive a charging current from a source external to the computing device 700. Computing device 700 may also include speakers 714 for providing audio output.

Various embodiments may include an apparatus comprising means for obtaining a gain of a first signal generated by one or more sensors, wherein the one or more sensors are placed on a body of a subject, means for determining a gain of a second signal generated by the one or more sensors, and means for generating a contact quality based on a comparison of the gain of the first signal and the gain of the second signal, wherein the contact quality corresponds to a level of contact between the one or more sensors and the body of the subject. In some embodiments, the means for generating the contact quality based on a comparison of a gain of the first signal and a gain of the second signal may include: means for comparing a gain of the first signal, a gain of the second signal, and one or more thresholds. Some embodiments may include means for adjusting one or more sensing modalities of one or more sensors based on the contact quality. In some embodiments, a low contact quality may indicate improper placement of one or more sensors, movement of the subject, or any combination thereof. Some embodiments may include means for filtering one or more measurements from the one or more sensors based on a comparison of the contact quality to at least one of the second thresholds, wherein the one or more measurements are associated with the second signal. In some embodiments, the means for obtaining, means for determining, and means for generating may operate after the variation in applied gain has stabilized to take into account the subject's body skin type and color.

Various embodiments may include an apparatus comprising means for determining a peak-to-peak voltage of a received signal from one or more sensors, and means for generating a contact quality based on the peak-to-peak voltage and one or more thresholds, wherein the contact quality corresponds to a level of contact between the one or more sensors and a body of a subject. Some embodiments may include means for filtering one or more measurements from one or more sensors associated with a received signal based on a comparison of a contact quality to one or more thresholds. In some embodiments, the contact quality may indicate improper placement of one or more sensors, movement of the subject, or any combination thereof.

Various embodiments may include a non-transitory medium having stored thereon processor-executable instructions configured to cause a processor of a device to perform operations comprising obtaining a gain of a first signal generated by one or more sensors, wherein the one or more sensors are placed on a body of a subject, determining a gain of a second signal generated by the one or more sensors, and generating a contact quality based on a comparison of the gain of the first signal and the gain of the second signal, wherein the contact quality corresponds to a level of contact between the one or more sensors and the body of the subject. In some embodiments, the stored processor-executable instructions may be configured to cause a processor of the device to perform operations such that generating the contact quality based on a comparison of the gain of the first signal and the gain of the second signal may include comparing the gain of the first signal, the gain of the second signal, and one or more thresholds. Some embodiments may include stored processor-executable instructions configured to cause a processor of a device to perform operations comprising adjusting one or more sensing modalities of one or more sensors based on contact quality. In some embodiments, the stored processor-executable instructions may be configured to cause a processor of the device to perform operations such that a low contact quality may indicate incorrect placement of the one or more sensors, movement of the subject, or any combination thereof. In some embodiments, the stored processor-executable instructions may be configured to cause a processor of a device to perform operations comprising filtering one or more measurements from one or more sensors based on a comparison of a contact quality to at least one of second thresholds, wherein the one or more measurements are associated with the second signal. In some embodiments, the stored processor-executable instructions may be configured to cause a processor of the device to perform operations such that obtaining, determining, and generating may be performed after the change in applied gain has stabilized to take into account the subject's body skin type and color.

Various embodiments may include a non-transitory medium having stored thereon processor-executable instructions configured to cause a processor of a device to perform operations including determining a peak-to-peak voltage of a received signal from one or more sensors, and generating a contact quality based on the peak-to-peak voltage and one or more thresholds, wherein the contact quality corresponds to a level of contact between the one or more sensors and a body of a subject. In some embodiments, the stored processor-executable instructions may be configured to cause a processor of a device to perform operations comprising filtering one or more measurements from one or more sensors associated with a received signal based on a comparison of a contact quality to one or more thresholds. In some embodiments, the stored processor-executable instructions may be configured to cause a processor of the device to perform operations such that the contact quality may indicate incorrect placement of the one or more sensors, movement of the subject, or any combination thereof.

Further, those skilled in the art will appreciate that the foregoing method descriptions and process flow diagrams are provided merely as illustrative examples and are not intended to require or imply that the steps of the various embodiments must be performed in the order presented. As will be appreciated by those skilled in the art, the order of the steps in the foregoing embodiments may be performed in any order. Words such as "after," "then," "next," etc. are not intended to limit the order of the steps; these words are simply used to guide the reader through the description of the method. Further, any reference to claim elements in the singular, for example, using the articles "a," "an," or "the," is not to be construed as limiting the element to the singular.

The various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the embodiments.

The hardware used to implement the various illustrative logics, logical blocks, modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. Alternatively, some steps or methods may be performed by circuitry that is specific to a given function.

The functions in the various embodiments may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored as one or more processor-executable instructions or code on a non-transitory computer-readable medium or a non-transitory processor-readable medium. The steps of a method or algorithm disclosed herein may be embodied in a processor-executable software module, which may reside on a non-transitory computer-readable or processor-readable storage medium. A non-transitory computer-readable or processor-readable storage medium may be any storage medium that can be accessed by a computer or a processor. By way of example, and not limitation, such non-transitory computer-readable or processor-readable media can comprise RAM, ROM, EEPROM, flash memory, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of non-transitory computer-readable and processor-readable media. Additionally, the operations of a method or algorithm may reside as one or any combination or set of codes and/or instructions on a non-transitory processor-readable medium and/or computer-readable medium, which may be incorporated into a computer program product.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the following claims and the principles and novel features disclosed herein.

Claims

1. A method for determining a measurement quality of one or more measurements from one or more sensors, comprising:

obtaining, at a processor, a gain of a first signal generated by the one or more sensors, wherein the one or more sensors are placed on a body of a subject, and wherein the gain of the first signal is related to a first time;

determining, at the processor, a gain of a second signal generated by the one or more sensors, wherein the gain of the second signal is related to a second time after the first time; and

generating, at the processor, a contact quality based on a comparison of the gain of the first signal and the gain of the second signal, wherein the contact quality corresponds to a level of contact between the one or more sensors and the body of the subject.

2. The method of claim 1, wherein the generating a contact quality based on the comparison of the gain of the first signal and the gain of the second signal further comprises: comparing the gain of the first signal, the gain of the second signal, and one or more thresholds.

3. The method of claim 1, further comprising:

adjusting one or more sensing modalities of the one or more sensors based on the contact quality.

4. The method of claim 1, wherein a low contact quality indicates improper placement of the one or more sensors, movement of the subject, or any combination thereof.

5. The method of claim 1, further comprising:

filtering one or more measurements from the one or more sensors based on a comparison of the contact quality to at least one of second thresholds, wherein the one or more measurements are associated with the second signal.

6. The method of claim 1, wherein the obtaining a gain of the first signal generated by the one or more sensors, the determining a gain of the second signal generated by the one or more sensors, and the generating the contact quality based on the comparison of the gain of the first signal to the gain of the second signal are performed after a change in applied gain has stabilized to account for a subject's body skin type and color.

7. An apparatus, comprising:

one or more sensors; and

a processor coupled to the one or more sensors, wherein the processor is configured to:

obtaining a gain of a first signal generated by the one or more sensors, wherein the one or more sensors are placed on a body of a subject, and wherein the gain of the first signal is related to a first time;

determining a gain of a second signal generated by the one or more sensors, wherein the gain of the second signal is related to a second time after the first time; and

generating a contact quality based on a comparison of the gain of the first signal and the gain of the second signal, wherein the contact quality corresponds to a level of contact between the one or more sensors and the body of the subject.

8. The device of claim 7, wherein the processor is configured such that generating a contact quality based on a comparison of the gain of the first signal and the gain of the second signal further comprises: comparing the gain of the first signal, the gain of the second signal, and one or more thresholds.

9. The device of claim 7, wherein the processor is further configured to adjust one or more sensing modalities of the one or more sensors based on the contact quality.

10. The apparatus of claim 7, wherein a low contact quality indicates improper placement of the one or more sensors, movement of the subject, or any combination thereof.

11. The device of claim 7, wherein the processor is further configured to filter one or more measurements from the one or more sensors based on a comparison of the contact quality to at least one of second thresholds, wherein the one or more measurements are associated with the second signal.

12. The device of claim 7, wherein the processor is configured such that the obtaining a gain of the first signal generated by the one or more sensors, the determining a gain of the second signal generated by the one or more sensors, and the generating the contact quality based on the comparison of the gain of the first signal to the gain of the second signal are performed after a change in applied gain has stabilized to account for a subject's body skin type and color.